Match each chemical reaction involving acids or bases listed on the left with its correct … — JAMB UTME

Match each chemical reaction involving acids or bases listed on the left with its correct characteristic observation or product on the right.

Reaction of dilute $HCl$ with $Na_2CO_3$ Effervescence of a gas ( $CO_2$ ) that turns lime water milky
Heating $NH_4Cl$ with aqueous $NaOH$ Evolution of a pungent gas ( $NH_3$ ) that turns moist red litmus paper blue
Reaction of dilute $H_2SO_4$ with zinc metalLiberation of a colorless gas ( $H_2$ ) that burns with a pop sound
Reaction of aqueous $NaOH$ with dilute $HNO_3$ Neutralization reaction forming a salt and water without gas evolution

Reaction of dilute

HCl

with

Na_2CO_3

pairs with effervescence of carbon(IV) oxide gas; heating

NH_4Cl

with aqueous

NaOH

pairs with evolution of pungent ammonia gas; reaction of dilute

H_2SO_4

with zinc metal pairs with liberation of hydrogen gas; and reaction of aqueous

NaOH

with dilute

HNO_3

pairs with neutralization forming a salt and water without gas evolution.

Each acid and base chemical property produces a distinct, diagnostic observation: acid + carbonate yields carbon(IV) oxide (

CO_2

), base + ammonium salt yields ammonia (

NH_3

), acid + reactive metal yields hydrogen (

H_2

), and acid + base (hydroxide) results in neutralisation forming salt and water.

Analyze acid-trioxocarbonate(IV) reaction property.

2HCl_{(aq)} + Na_2CO_{3(aq)} \rightarrow 2NaCl_{(aq)} + H_2O_{(l)} + CO_{2(g)}

. The evolved

CO_2

gas causes effervescence and turns lime water milky.

Acids liberate carbon(IV) oxide gas from trioxocarbonates(IV).

Analyze base-ammonium salt reaction property.

NH_4Cl_{(s)} + NaOH_{(aq)} \rightarrow NaCl_{(aq)} + H_2O_{(l)} + NH_{3(g)}

. Ammonia gas is pungent and alkaline, turning moist red litmus paper blue.

Soluble bases displace ammonia from ammonium salts when heated.

Analyze acid-metal displacement reaction property.

Zn_{(s)} + H_2SO_{4(aq)} \rightarrow ZnSO_{4(aq)} + H_{2(g)}

. Hydrogen gas burns with a pop sound.

Dilute acids react with metals above hydrogen in the electrochemical series to yield hydrogen gas.

Analyze acid-base neutralization property.

NaOH_{(aq)} + HNO_{3(aq)} \rightarrow NaNO_{3(aq)} + H_2O_{(l)}

. This is a neutralisation reaction yielding salt and water.

Soluble metal hydroxides react with acids to form salt and water only.

Chemical properties of acids and bases including gas evolution tests and neutralization

Question